Locking nut



FIG. 1 is a top perspective view of a locking nut according to my new design;

FIG. 2 is a side view thereof;

FIG. 3 is another side view thereof;

FIG. 4 is a top plan view thereof; and,

FIG. 5 is a bottom plan view thereof. 

The ornamental design for a locking nut, as shown and described. 